Fluid Phase Equilibria, Vol.233, No.2, 151-156, 2005
Characterizing phase transitions in liquid cesium by a soft-core and large-attraction equation of state
This paper investigates to identify phase transitions in condensed liquid cesium metal by considering the variation of intermolecular potential parameters E and r(m) in the whole liquid range, with E being the potential well-depth and r(m) the position of minimum potential. These parameters were obtained from the parameters of a new equation of state that was derived recently by using the characteristic potential function. By this method, transitions at about 575, 800, 1000, 1350, and 1650 K were identified. Transitions at 575, 800, and 1000 K are weak but, the one at 1350 K is very significant and has been explored experimentally and theoretically as the metal non-metal transition (MNMT), which is a phase transition before the critical condition dominates the thermodynamics. Also variations of the linear correlation coefficient of the isotherms generate a spot point pattern of these transitions. Our observations at 575 K for epsilon and r(m) are in accord with the anomalies in adiabatic thermal coefficient of pressure, density, viscosity, electrical conductivity, and structure factor. (c) 2005 Elsevier B.V. All rights reserved.
Keywords:liquid alkali metals;equation of state;liquid cesium;metal non-metal transition;second order phase transition;soft-core potential